package com.itheima;

import java.util.Comparator;
import java.util.TreeSet;

public class TreeSetDemo {
    public static void main(String[] args) {
        test1();
        int s =sum(1,2,3,4,5);
        System.out.println(s);
//        test0();
//        test1();
//        test2();
    }
    //ctrl+alt+m
    private static void test0() {
        //集合只能存储引用数据类型
        TreeSet<Integer> set1 = new TreeSet<>();
//        //1-->包装成Integer对象-->自动装箱
//        Integer i1 = Integer.valueOf(1);
//        int a = i1 + 2;
//        //自动拆箱
//        System.out.println(a);
        set1.add(5);
        set1.add(4);
        set1.add(2);
        set1.add(1);
        set1.add(3);
//        System.out.println(set1);
        //验证TreeSet的可排序特点(增强for循环)
        for (Integer integer : set1){
            System.out.println(integer);
        }
    }
    //c
    public  static  void  test1(){
        TreeSet<Student> set = new TreeSet<>();
        set.add(new Student("张三",19));
        set.add(new Student("李四",21));
        set.add(new Student("王五",16));
        set.add(new Student("赵六",20));

        for (Student student: set ){
            System.out.println(student.getName() + "-----" + student.getAge());
            System.out.println("-------------------");
        }

    }

    public static void test2() {
//        Comparator<Student> comparator = new Comparator<Student>() {
//            @Override
//            public int compare(Student o1, Student o2) {
//                //如果是正序排，那么o1 - o2
//                //倒序则o2 - o1
//
//                return o1.getAge() - o2.getAge();
//            }
//        };
//      Comparator<Student> comparator = (o1, o2) -> o1.getAge()-o2.getAge();

        Comparator<Student> comparator = (o1, o2) -> o1.getAge() - o2.getAge();
        TreeSet<Student> set = new TreeSet<>(comparator);
        set.add(new Student("张三",23));
        set.add(new Student("李四",21));
        set.add(new Student("王五",16));
        set.add(new Student("赵六",18));
        for(
                Student student:set )

        {
            System.out.println(student.getName() + "-----" + student.getAge());
            System.out.println("-------------------");
        }
    }
    //可变参数必须是形参的最后一个
    public static int sum(int... a){
        int total = 0;
        for (int i = 0; i < a.length; i++) {
            total += a[i];
        }
        return total;
    }


}
